It doesn’t matter. The suit is alleging that valve threatened to ban games if they were cheaper on other stores. Thats monopolistic price manipulation, and it’s illegal.

That is only true specifically for Steam keys and is a very important distinction. You can't sell your game cheaper with your free Steam keys on another store cheaper than Steam without giving Steam customers the same discount within a 'reasonable amount of time'.

Publishers/Developers are free to undercut Steam with non-Steam keys on other stores.

From their policy:

It's OK to run a discount for Steam Keys on different stores at different times as long as you plan to give a comparable offer to Steam customers within a reasonable amount of time.